NEW YORK (CBSNewYork) — Federal health officials have confirmed a second case of the potentially deadly MERS virus in the United States.

The virus has already killed a third of the 538 people worldwide confirmed to have MERS, mostly in Saudi Arabia.

As CBS 2’s Dr. Max Gomez reported Tuesday, MERS stands for Middle East Respiratory Virus — an illness that begins with a flu-like fever and cough, but can lead to pneumonia and death.

The questions now for U.S. health officials are how contagious is MERS and what precautions should Americans be taking?

Officials said the second confirmed case is located at a hospital in Orlando, Fla. The first was reported earlier this month in Indiana, involving a man who arrived from Saudi Arabia.

That patient has since recovered and was released from the hospital.

According to Dr. Gomez, the new patient is said to be a Saudi Arabian health care worker.

On May 1, the patient took four flights from Saudi Arabia to Orlando to visit relatives. During his trip, the patient developed a fever, chills, and a slight cough. Test results were positive for MERS.

Two health care workers in Orlando who came in contact with the MERS patient have developed flu-like symptoms, Gomez reported.

“One is being evaluated at home and the other is in hospital. Others are also being monitored. There is a 14-day quarantine period and they can return to work if disease and symptom free,” said Dr. Ken Michaels, of Orlando Health.

Even so, health officials stress that MERS does not appear to be highly contagious and that it requires close, perhaps prolonged, contact with an infected person to catch the virus.

So far no one who flew with either of the patients is known to have taken ill with MERS.

Additionally, officials at the Centers for Disease Control and Prevention said they know how to stop the spread of the virus through better hospital infection control.

“That’s been done in Indiana, it’s being done in Florida, and we’re working in the Middle East to help countries there improve infection control,” CDC Director Dr. Tom Frieden said.

The patient in Orlando is said to be doing well, and may be released soon, Gomez reported.

Doctors, however, say the wouldn’t be surprised if more cases surface in the U.S.

The CDC said these types of emerging illnesses are likely to continue to happen as viruses and bacteria mutate, become drug resistant, and more infectious to humans.

The list of worrisome diseases ranges from other respiratory viruses like SARS and Bird Flu as well as resurgent Tuberculosis to scary germs like Anthrax and Ebola.